From bc01d9ff93f350a35c51ddb75f81c2a6f663b1c1 Mon Sep 17 00:00:00 2001 From: Hugo Cornelis Date: Mon, 8 Jan 2024 15:24:30 +0100 Subject: [PATCH] image-host: refactor and protect for very long filenames This patch adds a function fit_image_read_key_iv_data that checks the return value of snprintf and allows to generate a sensible error message when generating binary images using filenames that are too long for the OS to handle. This is especially relevant for automated builds such as Buildroot and Yocto builds. Signed-off-by: Hugo Cornelis --- tools/image-host.c | 42 ++++++++++++++++++++++++++++++++---------- 1 file changed, 32 insertions(+), 10 deletions(-) diff --git a/tools/image-host.c b/tools/image-host.c index 90bc9f905f..b2a0f2e6d1 100644 --- a/tools/image-host.c +++ b/tools/image-host.c @@ -342,6 +342,28 @@ err: return ret; } +static int fit_image_read_key_iv_data(const char *keydir, const char *key_iv_name, + unsigned char *key_iv_data, int expected_size) +{ + char filename[PATH_MAX]; + int ret = -1; + + ret = snprintf(filename, sizeof(filename), "%s/%s%s", + keydir, key_iv_name, ".bin"); + if (ret >= sizeof(filename)) { + printf("Can't format the key or IV filename when setting up the cipher: insufficient buffer space\n"); + ret = -1; + } + if (ret < 0) { + printf("Can't format the key or IV filename when setting up the cipher: snprintf error\n"); + ret = -1; + } + + ret = fit_image_read_data(filename, key_iv_data, expected_size); + + return ret; +} + static int get_random_data(void *data, int size) { unsigned char *tmp = data; @@ -378,7 +400,6 @@ static int fit_image_setup_cipher(struct image_cipher_info *info, int noffset) { char *algo_name; - char filename[128]; int ret = -1; if (fit_image_cipher_get_algo(fit, noffset, &algo_name)) { @@ -415,17 +436,17 @@ static int fit_image_setup_cipher(struct image_cipher_info *info, goto out; } - /* Read the key in the file */ - snprintf(filename, sizeof(filename), "%s/%s%s", - info->keydir, info->keyname, ".bin"); info->key = malloc(info->cipher->key_len); if (!info->key) { fprintf(stderr, "Can't allocate memory for key\n"); ret = -1; goto out; } - ret = fit_image_read_data(filename, (unsigned char *)info->key, - info->cipher->key_len); + + /* Read the key in the file */ + ret = fit_image_read_key_iv_data(info->keydir, info->keyname, + (unsigned char *)info->key, + info->cipher->key_len); if (ret < 0) goto out; @@ -438,10 +459,11 @@ static int fit_image_setup_cipher(struct image_cipher_info *info, if (info->ivname) { /* Read the IV in the file */ - snprintf(filename, sizeof(filename), "%s/%s%s", - info->keydir, info->ivname, ".bin"); - ret = fit_image_read_data(filename, (unsigned char *)info->iv, - info->cipher->iv_len); + ret = fit_image_read_key_iv_data(info->keydir, info->ivname, + (unsigned char *)info->iv, + info->cipher->iv_len); + if (ret < 0) + goto out; } else { /* Generate an ramdom IV */ ret = get_random_data((void *)info->iv, info->cipher->iv_len); -- 2.39.5